Financial and personal transactions are being performed on computing devices at an increasing rate. However, the continual growth of such financial and personal transactions is dependent in part upon the establishment of security enhanced (SE) environments that attempt to prevent loss of privacy, corruption of data, abuse of data, etc. An SE environment may employ various techniques to prevent different kinds of attacks or unauthorized access to protected data or secrets (e.g. social security number, account numbers, bank balances, passwords, authorization keys, etc.). One type of attack that an SE environment may attempt to prevent is a sleep attack.
For example, many computing devices support a suspend-to-memory sleep state such as, for example, the S3 sleep state described in the Advanced Configuration and Power Interface (ACPI) Specification, revision 2.0, 27, Jul. 2000. Upon entering the suspend-to-memory sleep state, the computing device removes power from various components and/or subcomponents of the computing device but continues to power the system memory to retain the contents of the system memory. As a result of removing power, the computing device may remove power from circuitry used to protect secrets stored in the system memory. Upon waking from the sleep state, the computing device may return power to the circuitry used to protect secrets stored in system memory. However, after returning power, the protection circuitry may be in a reset state and may not actually protect secrets in system memory. An attacker may successfully gain access to stored secrets prior to re-establishing the protections provided by the protection circuitry.